Tasco(®), a product of Ascophyllum nodosum, imparts thermal stress tolerance in Caenorhabditis elegans

Tasco^®, a commercial product manufactured from the brown alga Ascophyllum nodosum, has been shown to impart thermal stress tolerance in animals. We investigated the physiological, biochemical and molecular bases of this induced thermal stress tolerance using the invertebrate animal model, Caenorhabiditis elegans. Tasco^® water extract (TWE) at 300 μg/mL significantly enhanced thermal stress tolerance as well as extended the life span of C. elegans. The mean survival rate of the model animals under thermal stress (35 °C) treated with 300 μg/mL and 600 μg/mL TWE, respectively, was 68% and 71% higher than the control animals. However, the TWE treatments did not affect the nematode body length, fertility or the cellular localization of daf-16. On the contrary, TWE under thermal stress significantly increased the pharyngeal pumping rate in treated animals compared to the control. Treatment with TWE also showed differential protein expression profiles over control following 2D gel-electrophoresis analysis. Furthermore, TWE significantly altered the expression of at least 40 proteins under thermal stress; among these proteins 34 were up-regulated while six were down-regulated. Mass spectroscopy analysis of the proteins altered by TWE treatment revealed that these proteins were related to heat stress tolerance, energy metabolism and a muscle structure related protein. Among them heat shock proteins, superoxide dismutase, glutathione peroxidase, aldehyde dehydrogenase, saposin-like proteins 20, myosin regulatory light chain 1, cytochrome c oxidase RAS-like, GTP-binding protein RHO A, OS were significantly up-regulated, while eukaryotic translation initiation factor 5A-1 OS, 60S ribosomal protein L18 OS, peroxiredoxin protein 2 were down regulated by TWE treatment. These results were further validated by gene expression and reporter gene expression analyses. Overall results indicate that the water soluble components of Tasco^® imparted thermal stress tolerance in the C. elegans by altering stress related biochemical pathways.     

Effects of light intensity and plant size on the foliar nutrient content of field‐grown metrosideros polymorpha seedlings

Foliar concentrations of eight essential elements were measured in three sizes of Metrosideros polymorpha tree seedlings that had been subjected to five different light levels as part of a canopy thinning experiment in a Hawaiian montane rain forest. Most element concentrations were reduced by increased light intensity, but this was statistically significant only for Ca, Mg, and Zn. N and P concentrations markedly decreased with increasing plant size. No element exhibited consistent concentration increases in response to higher light or greater size. As in temperate herbaceous species, lower element concentrations associated with larger or more illuminated plants may represent a dilution effect related to the cumulative amount of C fixed in the lifetime of individual leaves. The rapid growth of newly unshaded seedlings may result in nutrient limitations in seedlings not rooted in mineral soil.     

Influence of Stubble Thickness, Carbohydrate Content and Leaf Senescence on Ratoon Rice

Experiment conducted with nine rice varieties during Pishanum season of 1989–90 revealed that Co 37 performed better in ratoon crop and recorded 3.2 t/ha grain yield. It was evident that the ratooning ability was influenced by stem thickness of stubble, carbohydrate content and leaf senescence of main crop. The study also suggests that by maintaining higher seed size and productive tiller in ratoon crop, there is ample possibilities to increase grain yield.     

Developmental changes of seminiferous tubule in prenatal, postnatal and adult testis of bonnet monkey (Macaca radiata)

This paper is a part of our study on the male reproductive system of bonnet monkey. The developmental changes in testis of bonnet monkey were studied qualitatively and quantitatively, at the light microscopy level. Testicular development appears to primarily involve tubular growth that starts immediately after birth. There is a gradual increase in the number of tubules in the prenatal to neonatal stage in testis, without an increase in the volume. Increase in the number of tubules in the neonatal testis was achieved by an increase in the length of the tubules and reduction in the interstitial proportion. Scattered spermatogonial cells in the tubules of neonatal testis indicate the rapid growth rate of the tubules. Increase in tubular length along with diameter seems to be a continuous process until puberty. This is the first report on the developmental changes in the testis during fetal, postnatal and adult stages in the bonnet monkey.     

Analgesic activity of methanol extract of Aegle marmelos leaves

The methanol extract of leaves of Aegle marmelos at a dose level of 200 and 300 mg/kg showed significant analgesic activity on acetic acid-induced writhing and tail flick test in mice.     

Variability for quantitative traits in exotic hybrid germplasm of sugarcane

The foreign hybrid collection of sugarcane germplasm comprising 399 clones representing 10 geographical groups, was evaluated for nine yield and quality characters, in relation to their place of origin. Discriminant function analysis showed that all the nine variables contributed significantly to the discrimination of the groups, the maximum contribution being cane height. The overall percentage of correct classification was only 48%, with a range from 32% to 73% with respect to individual groups. This suggests an underlying genetic similarity among the groups, which stem largely from their common genetic base. The exceptions were the Hawaii and Mauritius groups, which had distinct identities. The Hawaii group was the most productive group, having maximum yield and sucrose potential. The Puerto Rico group was the best source for juice sucrose. Australian varieties bred for high juice quality did not show the expected level of juice sucrose in the present study. The use in breeding programmes of Hawaiian varieties, which have a broader genetic base and high yield and quality potential, might impart better productivity to commercial varieties.